title: Purification and characterization of two types of alkaline serine proteases produced by an alkalophilic actinomycete.
abstract: Two types of alkaline serine proteases were isolated from the culture filtrate of an alkalophilic actinomycete, Nocardiopsis dassonvillei OPC-210. The enzymes (protease I and protease II) were purified by acetone precipitation, DEAE-Sephadex A-50, CM-Sepharose CL-6B, Sephadex G-75 and phenyl-Toyopearl 650 M column chromatography. The purified enzymes showed a single band on sodium dodecyl sulphate polyacrylamide gel electrophoresis. The molecular weights of proteases I and II were 21,000 and 36,000, respectively. The pIs were 6.4 (protease I) and 3.8 (protease II). The optimum pH levels for the activity of two proteases were pH 10-12 (protease I) and pH 10.5 (protease II). The optimum temperture for the activity of protease I was 70 degrees C and that for protease II was 60 degrees C. Protease I was stable in the range of pH 4.0-8.0 up to 60 degrees C and protease II was stable in the range of pH 6.0-12.0 up to 50 degrees C.
authors.affiliation: Osaka University of Pharmaceutical Sciences, Matsubara, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Tsujibo
authors.forename: K
authors.initials: K
authors.lastname: Miyamoto
authors.forename: T
authors.initials: T
authors.lastname: Hasegawa
authors.forename: Y
authors.initials: Y
authors.lastname: Inamori
mesh_terms: D000192:Actinomycetales / Q000145:classification / Q000201:enzymology*; D002413:Cations, Divalent / Q000494:pharmacology; D002614:Chelating Agents / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel; D006863:Hydrogen-Ion Concentration; D007526:Isoelectric Point; D008970:Molecular Weight; D012697:Serine Endopeptidases / Q000302:isolation & purification* / Q000378:metabolism; D013696:Temperature
chemical_list: D002413:Cations, Divalent; D002614:Chelating Agents; D012697:Serine Endopeptidases; C032923:microbial serine proteinases